Publicaciones

Knowledge on the spatial ecology of invasive predators positively contributes to optimizing their management, especially when involving cryptic and secretive species, such as snakes. However, this information is lacking for most invasive snakes, particularly on islands, where they are known to cause severe ecological and socio-economic impacts. This research is focused on assessing the spatial ecology of the California kingsnake (Lampropeltis californiae) on Gran Canaria to strengthen management actions. We monitored 15 radio-tagged individuals once per day on 9–11 days per month from July 2020 to June 2021 to calculate the species' home range and describe annual activity patterns in the invaded range. To account for the species' diel activity during the emergence period, we additionally monitored snakes from January to May 2021 during three consecutive days per month in four different time intervals each day. We detected movement (consecutive detections at least 6 m apart) in 31.68% of the 1146 detections during the whole monitoring period. Movements most frequently detected were shorter than 100 m (82.24%), and among them the range 0–20 m was the most recurrent (27.03%). The mean distance of movement was 62.57 ± 62.62 m in 1–2 days. Average home range was 4.27 ± 5.35 ha—calculated with the Autocorrelated Kernel Density Estimator (AKDE) at 95%—and did not significantly vary with SVL nor sex. We detected an extremely low value of motion variance (0.76 ± 2.62 σ2m) compared to other studies, with a general inactivity period from November to February, January being the less active month of the year. Diel activity was higher during central and evening hours than during early morning and night. Our results should be useful to improve control programs for this invasive snake (e.g., trap placement and visual survey guidance) on Gran Canaria. Our research highlights the importance of gathering spatial information on invasive snakes to enhance control actions, which can contribute to the management of secretive invasive snakes worldwide.

Volcanic plume composition is strongly influenced by both changes in magmatic systems and plume-atmosphere interactions. Understanding the degassing mechanisms controlling the type of volcanic activity implies deciphering the contributions of magmatic gases reaching the surface and their posterior chemical transformations in contact with the atmosphere. Remote sensing techniques based on direct solar absorption spectroscopy provide valuable information about most of the emitted magmatic gases but also on gas species formed and converted within the plumes. In this study, we explore the procedures, performances and benefits of combining two direct solar absorption techniques, high resolution Fourier Transform Infrared Spectroscopy (FTIR) and Ultraviolet Differential Optical Absorption Spectroscopy (UV-DOAS), to observe the composition changes in the Popocatépetl’s plume with high temporal resolution. The SO2 vertical columns obtained from three instruments (DOAS, high resolution FTIR and Pandora) were found similar (median difference <12%) after their intercalibration. We combined them to determine with high temporal resolution the different hydrogen halide and halogen species to sulfur ratios (HF/SO2, BrO/SO2, HCl/SO2, SiF4/SO2, detection limit of HBr/SO2) and HCl/BrO in the Popocatépetl’s plume over a 2.5-years period (2017 to mid-2019). BrO/SO2, BrO/HCl, and HCl/SO2 ratios were found in the range of (0.63 ± 0.06 to 1.14 ± 0.20) × 10−4, (2.6 ± 0.5 to 6.9 ± 2.6) × 10−4, and 0.08 ± 0.01 to 0.21 ± 0.01 respectively, while the SiF4/SO2 and HF/SO2 ratios were found fairly constant at (1.56 ± 0.25) × 10−3 and 0.049 ± 0.001. We especially focused on the full growth/destruction cycle of the most voluminous lava dome of the period that took place between February and April 2019. A decrease of the HCl/SO2 ratio was observed with the decrease of the extrusive activity. Furthermore, the short-term variability of BrO/SO2 is measured for the first time at Popocatépetl volcano together with HCl/SO2, revealing different behaviors with respect to the volcanic activity. More generally, providing such temporally resolved and near-real-time time series of both primary and secondary volcanic gaseous species is critical for the management of volcanic emergencies, as well as for the understanding of the volcanic degassing processes and their impact on the atmospheric chemistry.

Naegleria fowleri is an opportunistic protozoon that can be found in warm water bodies. It is the causative agent of the primary amoebic meningoencephalitis. Focused on our interest to develop promising lead structures for the development of antiparasitic agents, this study was aimed at identifying new anti-Naegleria marine natural products from a collection of chamigrane-type sesquiterpenes with structural variety in the levels of saturation, halogenation and oxygenation isolated from Laurencia dendroidea. (+)-Elatol (1) was the most active compound against Naegleria fowleri trophozoites with IC50 values of 1.08 μM against the ATCC 30808™ strain and 1.14 μM against the ATCC 30215™ strain. Furthermore, the activity of (+)-elatol (1) against the resistant stage of N. fowleri was also assessed, showing great cysticidal properties with a very similar IC50 value (1.14 µM) to the one obtained for the trophozoite stage. Moreover, at low concentrations (+)-elatol (1) showed no toxic effect towards murine macrophages and could induce the appearance of different cellular events related to the programmed cell death, such as an increase of the plasma membrane permeability, reactive oxygen species overproduction, mitochondrial malfunction or chromatin condensation. Its enantiomer (−)-elatol (2) was shown to be 34-fold less potent with an IC50 of 36.77 μM and 38.03 μM. An analysis of the structure–activity relationship suggests that dehalogenation leads to a significant decrease of activity. The lipophilic character of these compounds is an essential property to cross the blood-brain barrier, therefore they represent interesting chemical scaffolds to develop new drugs.

Leishmaniasis and Chagas disease affect millions of people worldwide. The available treatments against these parasitic diseases are limited and display multiple undesired effects. The brown alga belonging to the genus Gongolaria has been previously reported as a source of compounds with different biological activities. In a recent study from our group, Gongolaria abies-marine was proven to present antiamebic activity. Hence, this brown alga could be a promising source of interesting molecules for the development of new antiprotozoal drugs. In this study, four meroterpenoids were isolated and purified from a dichloromethane/ethyl acetate crude extract through a bioguided fractionation process targeting kinetoplastids. Moreover, the in vitro activity and toxicity were evaluated, and the induction of programmed cell death was checked in the most active and less toxic compounds, namely gongolarone B (2), 6Z-1′-methoxyamentadione (3) and 1′-methoxyamentadione (4). These meroterpenoids triggered mitochondrial malfunction, oxidative stress, chromatin condensation and alterations of the tubulin network. Furthermore, a transmission electron microscopy (TEM) image analysis showed that meroterpenoids (2–4) induced the formation of autophagy vacuoles and ER and Golgi complex disorganization. The obtained results demonstrated that the mechanisms of action at the cellular level of these compounds were able to induce autophagy as well as an apoptosis-like process in the treated parasites.

Harmful algal blooms (HABs) and their impact in aquaculture, services and aquatic ecosystems in coastal areas are a major concern. The occurrence of these natural phenomena is expected to increase due to the growing pressure of anthropogenic activities, the projected climate trends, and their effects in the marine environment (Kazmi et al., 2022; Zhang et al., 2022). Methodological advances in monitoring systems for a fast and precise detection of biotoxins, together with a better knowledge on oceanographic conditions suitable for development of HABs, contributed to a more efficient and cost-effective management of aquaculture and fishery resources (Ruiz-Villarreal et al., 2022).

The number of craft breweries and the volume of craft beer produced globally is growing exponentially. However, little is known about their differences with mainstream beers regarding mycotoxin profile, pesticide and pollutant residues and elemental composition. Given that beer is one of the most consumed beverages worldwide, it is important to shed light on its toxicological profile. In this study, samples of 23 craft beers and 19 mainstream Spanish beers were collected to perform a comparative analysis including 8 mycotoxins, 225 pesticide residues and 50 POPs, and 50 elements. Mycotoxins were not detected in craft beers, while 100% of mainstream beers presented at least one mycotoxin. In contrast, craft beers contained higher average pesticide residues than their mainstream counterparts, although significant differences were only found in Mepiquat and Metrafenone content. No persistent organic pollutants were detected in any sample. The elemental composition presented differences between the two groups both in the concentration of elements and their hierarchy. In conclusion, the toxicological profile of all beers was safe and is unlikely to constitute a hazard to consumer health. Craft beers present significant differences from their mainstream counterparts in all the dimensions explored.

En este tutorial se muestra con el ejemplo de los éteres propargílicos vinílicos, bloques sintéticos multifuncionales, como es posible instrumentalizar la reactividad emergente de la combinación de sus grupos funcionales para el diseño y desarrollo de procesos dominó (cascada) ramificados para la generación de complejidad molecular orientada a la diversidad.

Rabbits have travelled with humans to the most remote archipelagos, having been introduced on at least 800 islands worldwide. This herbivore has caused a devastating effect on endemic insular plants, causing changes in species composition, cascading extinctions and disruption of native seed dispersal systems worldwide. However, its ecological impacts as disrupting native seed dispersal systems have not been studied from a holistic perspective in any of the archipelagos where rabbits were introduced. Here, we assess the role of rabbits as frugivores and seed-dispersers on the most extensive and diverse island of the Canary Archipelago, Tenerife, across its five main vegetation zones represented in an altitudinal gradient 0–3715 m a.s.l. To this end, 120 transects per vegetation zone were conducted (August 2020–November 2021) to collect fresh faecal samples from a total of 244 latrines. They consisted of 29,538 droppings in which we found seeds from 73 plant species, 29 of which were identified to species level (13 endemic, eight natives and eight introduced by humans). About 70% of the seeds were identified as fleshy-fruited plant species while the remaining nine were dry fruits. Of the former, only nine showed a percentage of intact seeds greater than 75%, another nine species between 50 and 75%, and three lower than 50%. The digestive effect of rabbits on seedling emergence was generally low, compared to that produced by native seed dispersers. Since fleshy-fruited plants and rabbits have not been linked in their evolutionary history in the Canaries, the former seems to have their own legitimate seed dispersers.

A recurring feature of oceanic archipelagos is the presence of adaptive radiations that generate endemic, species-rich clades that can offer outstanding insight into the links between ecology and evolution. Recent developments in evolutionary genomics have contributed towards solving long-standing questions at this interface. Using a comprehensive literature search, we identify studies spanning 19 oceanic archipelagos and 110 putative adaptive radiations, but find that most of these radiations have not yet been investigated from an evolutionary genomics perspective. Our review reveals different gaps in knowledge related to the lack of implementation of genomic approaches, as well as undersampled taxonomic and geographic areas. Filling those gaps with the required data will help to deepen our understanding of adaptation, speciation, and other evolutionary processes.

Aim: How spatial, historical and ecological processes drive diversity patterns remains one of the main foci of island biogeography. We determined how beta diversity varies across spatial scales and among organisms, disentangled the drivers of this variation, and examined how, consequently, biogeographic affinities within and among archipelagos vary among land plants.